Disappearing type pin feed



July s, 1958 2 Sheets-Sheet 1 Filed Aug. 31, 1955 y 1953 J. E. EUTHDISAPPEARING TYPE PIN FEED 2 Sheets-Sheet 2 Filed Aug. 51, 1955 v FIE-14FIE. E

2,842,247 DISAPPEARING TYPE PIN FEED John E. Euth, Chicago, 111.,assignor to Uarco, Incorporated, a corporation of Illinois ApplicationAugust 31, 1955, Serial No. 531,669

6 Claims. (Cl. 197-433) This invention relates to a pin-type feed unitfor use with platens of writing machines and more particularly to a newand improved pin feed of the type in which the pins disappear below thesurface of the unit in travel ing around it.

Typewriter platens as well as the platens of other business machines areoften equipped with a pin feed to engage marginally punched stationery.The platens generally also are provided with the usual friction rollerfeeds for use with stationery not equipped with punched margins. Theparticular disappearing pin-type of feed with which this invention isconcerned employs a cam for radially reciprocating the pins outwardlyfrom the surface of the platen. The greatest extension of the pins isgenerally at the line of writing with the pins retracting beyond thisline. Such units have, in the past, been equipped generally with ashifting mechanism permitting the turning of the cams so that the pinswill extend outwardly at a point away from the line of the stationerypassing around the platen so that the platen is equally well usable witheither type of stationery referred to.

In the past, considerable difiiculty has been encountered with pin feedsof the disappearing type. The most prevalent constructions have employeda cam in the form of a rail serving both to support the pins and toguide them in their radial movement. Some pins have been provided withoutwardly extending bosses to engage the rail while in other units thepins have been provided with a notch near their inner end to engage andride upon the rail. Experience has taught that these pins often catch onthe cam rail so that when forced forward by the operator, the pins havebeen broken and subsequently lost. It is extremely difficult to locatesuch trouble in advance since the unit is closed except for the openingsthrough which the pins extend, thus giving the manufacturer no chance toobserve which of the many pins is causing the difficulty. I

It is therefore the principal object of this invention to provide a newand improved disappearing pin-type feed for punched stationery.

Another object of the invention is to provide a unit which may be easilymanufactured so as to be smooth running over a greater useful life.

A further object is to provide a disappearing pin-type feed unit inwhich the pins are provided with bearings guiding their radial movementand a cam and follower structure not subject to the usual seizing orsticking heretofore found in prior art structures.

Other objects, features and advantages of the present invention will beapparent from the following description of a preferred embodiment inwhich:

Figure 1 is a fragmentary sectional view through the centerline of oneend of a platen having the unit of this invention therein;

Figure 2 is a sectional view through the unit taken substantially alongline 22 in Figure 1 looking toward the pins;

Figure 3 is a sectional view through the unit taken Q United StatesPatent 2 L substantially along line 3-3 in Figure 1 looking toward thecam plate;

Figure 4 is a fragmentary sectional view through the unit takensubstantially along line 4-4 in Figure 1;

Figure 5 is a fragmentary end elevational view of the unit illustratingthe control plates;

Figure 6 is an elevational view of. a pin removed from the unit; and

Figure 7 is an end view of the pin illustrated in Figure 6. a

As illustrated in Figure 1, the present pin feeding unit is mounted uponthe shaft 8 of a typewriter'platen carrying an outer rubber sleeve 9 ofthe platen itself. The outer end portion 8a of the shaft, which is shownas broken, would ordinarily carry'a knurled end knob by which theoperator could manually turn the platen; While the invention is shown asinstalled upon a typewriter platen, it is equally applicable to anyround platen found in the usual business machines.

In operation, a pin carrier is made to turn with the platen so that thepins are carried with the platen surface and retain their positionrelative to the platen. The pin carrier has bearings for the pins andrevolves next to a stationary cam covering plate which has a cam whichcauses the pins to reciprocate radially. The pins reciprocate to anextent which will extend them outwardly from the platen surface asufiicient distance to engage feed holes in stationery and then to fullyretract below the surface of the platen. In the present invention, theentire pin feed unit is mounted upon a metal sleeve 10 which fits fairlyclosely around the platen shaft 8. A pin carrier, generally indicated11, is mounted to revolve with the sleeve 10 and with the platen surface'9. The pin carrier has a cylindrical part 12 which fits inside of therubber covering 9 of the platen and against the metal sleeve 10 whichsupports the entire unit. The pin carrier is held in place by awasher-like plate 13 abutting the end of the sleeve 10 and fastened tothe cylindrical portion 12 of the pin carrier by a pair of cap screws 14on diametrically opposite sides of the shaft of the platen. Thecylindrical portion 12 also has a radial bore 24 in which a driving pin15 having a square head 16 is mounted so that a positive driveconnection will be made between the pin carrier and the rubber surfacesleeve 9 of the platen. An appropriate slot is made in the underside ofthe sleeve 9 to accommodate the square head of the driving pin The pinsof the feeding member are housed in a radially extending portion 20 ofthe pin carrier 11. As better seen in Figure 2, the radially extendingportion 20 of the pin carrier is provided with. radial square grooves 21which form bearings for pins 25. The slots 21 are milled in the face ofthe radially extending portion 20' of the carrier and may be ten innumber, as illustrated in Figure 2, or in other units may be nine oreleven, equally spaced around the face thereof.

The pins 25 are made of squarestock in a screw machine operation whichforms a rounded end 26 which is smooth in contour. After the pins havebeen formed of the square stock, generally of tool steel, they areplaced in a jig and cross drilled to form an aperture 27 for thereception of a cam follower pin 28 placed therein with a press fit. Allof the pins 25 used in the units are of equal length with the unit beingnine, ten or eleven pin type. The stock from which the pins are made iscontrolled in thickness quite accurately so that the slots 21 may bemilled about .002" over the size of the pins. In this manner, a veryaccurate bearing surface for the square pin is provided in the pincarrier 11.

As mentioned above, the bearings for the pins are open on the face ofthe pin carrier and the pins reciprocate in the slots. A four-sidedapertured bearing is proular attention or service.

vided for the pins by closing the open side of the slots in place.

The pins are made to reciprocate in their respective bearings by the camfollower pins 28 riding in a cam groove 31 milled in the face of thecover plate 30. As

seen in Figure 3, the follower pins 28 are spaced evenly around thecenterline of the shaft 8 and each is in the cam grove 31, theshape ofwhich is illustrated.

In operation, the cam cover plate 30 rides on the metal sleeve and isheld in place therein by a ring retainer 32 abutting against a clamp 33having a shoulder 34 abutting against the ring. The clamp 33,illustrated more clearly in Figure 4, bears down against a slotted endportion 10a of the sleeve so that it may grip upon the shaft 8 toperform the function of making the sleeve 10 rotate with the shaft andto hold the assembly of pin carrier and cam cover plate together againstthe washer retainer 13 on the opposite end of the sleeve 10. The methodused for holding the cam plate stationary while the pin carrier turns isa combination of two control plates mounted on the outer end adjacentthe cam plate. One plate 35, better seen in Figure 5, is mounted againstthe cover plate and held stationary with respect thereto by a screw 36fastened to the cover plate through an arcuate slot 37 permitting someadjustment of the plate 35 in position relative to the cam plate. Asecond control plate 38 has an upper open slot 39 for engaging the usualcross rod on a platen used to hold the paper guide. This plate 38 isthus held stationary in position relative with the platen. A latchmember 40 is secured to the plate 38 by rivet 41 having a spring washer42 under its head and a detent for engaging notches 43 in the controlplate 35 to in turn hold the cam plate stationary. Upon manual releaseof the latch by grasping the handle 44, the plate 35 can be manuallyturned to bring the notch 43 down to the latch member, thus shifting theposition of the cam plate 30 relative to the platen. In this manner, theapex portion, generally indicated 31a, of the cam groove, as seen inFigure 3, can be shifted relative to the line of writing on the platen.If the pins are not needed, they may be caused to extend outwardly fromthe platen at a point that will not contact the stationery.

The complete unit may be removed from the end of a platen quite readilyand easily by loosening the clamp 33 by its clamping screw 33asufliciently to allow the metal sleeve 10 to be slipped longitudinallyover the shaft 8 of the platen. It has been found, however, that in thepresent unit there is little need for removing the unit once installedsince there is practically no binding of the pins in the unit at anytime even though service of the unitis neglected. The combination of thesquare pins riding in bearings for practically their full length oftravel and the use of the round pin followers riding in a milled camgroove has eliminated all sticking or catching of the pins. Acceleratedlife tests have indicated that the unit is particularly adapted for longlife and use without partic- The manufacture of the unit, particularlyin the assembly stage, is facilitated by the structure of the unit. Nodifiiculties have been encountered in getting the unit to run smoothlyafter assembly.

The foregoing detailed description has been given for clearness ofunderstanding only, and no unnecessary limitations should be understoodtherefrom, for some modifications will be obvious to those skilled inthe art.

I claim:

1. A pin type stationary feed unit, comprising: a pin carrier having aplurality of apertured bearings extending radially; pins reciprocallymounted in said bearings with the pins and bearings having polygonalcross sec tions preventing rotary movement of the pin in the hearing,said bearings being elongated and providing the sole guiding support forthe pins; a laterally extending stud on each pin; and a plate having acam groove therein receiving said studs for moving the pins radiallyupon relative rotation of the carrier and plate.

2. A pin type stationary feeding unit, comprising: a pin carrier havingradially extending open grooves in one side; a cover plate closing theopen side of said grooves to form apertured radially extending elongatedbearings; a feeding pin slidably supported in each bearing with the pinand bearing having complementary polygonal cross sections; and alaterally extending stud on each pin with the cover plate having a camgroove receiving the studs for moving the pins radially in theirrespective bearings.

3. A pin type feeding unit for continuous form stationery, comprising: apinwheel and a cover plate having radially extending adjacent faces,said pinwheel face having a plurality of radial grooves therein closedon one side by said cover plate face, said grooves each being shaped toform an elongated square bore apertured hearing; a square pin slidablein each bearing; a laterally extending stud secured to each pin; andsaid cover plate having a cam groove therein receiving said studs formoving the pins radially in said bearings upon relative rotation of thepinwheel and plate.

4. A pin type feeding unit for continuous form stationery, comprising: apinwheel and a cover plate having adjacent faces, said face of thepinwheel having radial grooves, said cover plate face closing one sideof said grooves and the grooves being shaped to form a plurality ofsquare bores cooperatively with the cover plate; a square pin in eachbore having continuous bearing support in the bore for radialreciprocation; and a round laterally extending stud on each pin withsaid cover plate having a cam groove in said face receiving said studsfor moving the pins radially upon rotation of the pinwheel relative tosaid cover plate.

5. A pin type stationery feeding unit, comprising: a pinwheel and acover plate mounted side by side for relative rotation; a plurality offeeding pins mounted in the pinwheel and having continuous slidingbearing support therein to confine movement of the pins to radialreciprocation; and a laterally extending stud on each pin extendingoutwardly from the pinwheel, said cover plate having a cam groove withcontinuous side walls for abutting said studs for moving the pinsradially upon rotation of the pinwheel'relative to said cover plate, andsaid studs having rounded surfaces engaging said cam groove side wallsto prevent binding of the studs in the groove during said rotation.

6. A stationery feeding unit as specified in claim 5 wherein the bearingsupport for the pins comprises square bores formed cooperatively bygrooves in the pinwheel and a flat face of the cover plate and the pinsare square with only sliding tolerance between the pins and bores.

References Cited in the file of this patent Davidson July 13, 1954

